This study attempts to elucidate the significance of cooperative learning via visualization of the development of the students' recognition process during a classroom discussion. Toward this end, this study makes improvement on the analysis method, termed intermediate factors (Chu-kan-ko), by applying "Ontology," a notational system in information science. Intermediate factors is an analysis method developed by the research division of Methods of Education, Graduate School of Education and Human Development, Nagoya University. This research division has been conducting studies on the relational structures of pedagogical factors, developing various analysis methods for transcriptbased lesson analysis. It is expected that applying Ontology to intermediate factors may clarify further students' cooperative learning process. The authors analyze a cooperative learning lesson by interpreting a lesson transcript and utilizing the interpretations of Ontology. For this case analysis, a social studies lesson of 3rd grade is selected. In the lesson, students learn about local industry through investigating K's gloves factory which locates within students' living area and produces high quality and eco gloves. Students discussed on the significance of the factory in the classroom after observing the factory, surrounding shops, and interviewing locals. Firstly, 3 hermeneutic case analyses are conducted based on interpretations. Each case is characterized as follows: (1) Although students arrived at different conclusions, they used the same facts as grounds for their opinions. (2) Some students made their own conclusions by reasoning, transforming the information into a quantitative form. (3) Due to an earnest concern address the problem of K's gloves factory, students developed recognition of self learning by utilizing critical thinking. Secondly, the above hermeneutic case analyses based on analysists' interpretation are reconstructed by Ontology. As a result, it is found that students develop ideas through assimilating other students' ideas; new concepts introduced provide stimulation as indicated by student utterances. It can be seen from this study that cooperative learning has the potential to create a discourse space in which students interact, expanding and deepening their own thoughts by adding new ideas and perspectives. Future research might compare the notational systems of this study with the previous analysis method produced by the Division of the Methods of Education, Nagoya University, examining the possibility to integrate and improve the method of transcript-based lesson analysis approach.